Printing techniques in the packaging industry

 

There are five main printing techniques most commonly used in the packaging industry. Each type has its own pros and cons. Includes: offset lithography, flexography, Digital (Inkjet), Rotogravure, and Silkscreen.

 

Offset lithography

Offset printing is now fully known as offset lithography printing, which is a printing technique that combines two older printing techniques. These are offset and lithography, both of which are indirect embossing techniques. This is the most prominent printing technique in the packaging industry today. It's all about flexibility in printing and high image quality.

Principle of offset printing

The printout (usually aluminum foil) is engraved with the image to be printed, ink is rolled, printed on another rubber roller and then from the rubber through the printing surface. This print surface must be flat.

Offset printing ink is an oil-based, water-repellent ink. A humidification system must be provided to apply water to the non-ink area. The image area can receive ink and the non-image area repels ink and gets wet.

Printers that do not use a humidification system are called dry offset printers. Instead of water, the non-printed area is coated with ink-free silicone.

Advantage

Print on many materials such as paper, cartons, plastic, metal ...

High print quality.

Coatings can be applied as gloss or matte.

Color transitions are very smooth.

High input and printing speed. There are machines that can have speeds up to 15,000 prints per hour.

Defect

Price. Different products require different printing.

The printing surface must be flat.

There is no profit in doing it in low quantities

Flexography

Flexography or flexographic printing is the modern printing technique of letterpress. Its name is derived from the fact that the print is embossed on flexible plates.

 

 

Principle of flexo printing

While offset is printing indirectly through a rubber sheet, flexo is the process of printing directly onto the printed surface.

 

The print is usually etched onto the print by laser. Ink is applied to the printout via an anilox roller and excess ink is scraped off with a blade. The ink is then applied to the print surface and coatings can be added.

 

Initially, flexo could only print medium-quality images. But after the development of digital, the quality of printing has improved a lot.

 

Advantage

Various printing materials, cartons, paper, plastic...

Low cost per product.

Investment costs (prints, ink, etc.) are low.

Defect

Quality is lower than offset.

The color gradient is not equal to the offset.

The photo cannot be printed.

 

Rotogravure

 

Rotogravure in Vietnam is called gravure printing. This is a gyroscopic printing technique that prints directly onto the printed surface. This is the perfect printing technique for newspapers and magazines.

 

 

Gravure printing principle

This is a printing process that uses multiple rotary axes with the image imprinted onto the surface. The ink will be held in the imprints and pressed directly onto the printing surface.

 

The print roller has multiple levels of depth to accommodate the ink. So more ink will be contained in the deeper area and the ink will be darker in that area. On the contrary, the ink will be lighter in deeper places.

 

This printing technique is now being phased out by offset (for publications) and flexo/digital (for packaging).

 

Advantage

Low cost for bulk production.

Extremely high print quality.

The printing roller can be preserved for a long time.

Defect

There are very few coating options.

Only profitable when printing in bulk.

Investment costs (printing shaft, ink, etc.)

Conclude

Each printing technique has its own advantages and disadvantages, and is also suitable for different print volumes. Divided by print quality, the following list can be considered:

Paper bag: offset, flexo

Plastic (Plastic) Flexo bag, screen

Reusable bag: Screen

Cover: Offset, Digital, Gravure, Screen

Carton: Flexo, Digital

Hard Box: Offset

Stickers: Offset, Digital, Screen

Other factors that can be considered include: print volume, color titer, capital.

Hopefully, through this article, you can choose the right printing method for the quality and quantity of printing you need. For all consulting, design and packaging needs, please contact:

Tam Thanh Industrial Joint Stock Company

PP factory: Ngach 28/66 Ngoc Dong Hamlet – Da Ton Commune – Gia Lam District – Hanoi City

Website: https://tamthanh.com.vn

baobitamthanh.com

Email :tamthanhbaobi@gmail.com

Hotline: 0904 592 386

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